An actor and writer who has appeared in various television programmes and films including The Office (UK TV series), The Catherine Tate Show and Smack the Pony. Movie credits include Life and Death of Peter Sellers, The Duchess (film) and Vanity Fair (2004 film). He has also written for television shows such as The Catherine Tate Show, Alistair MacGowan, Johnny Vaughan and for Dara Ó Briain on Live Floor Show. In 2012, Mackinnon was selected to play Sir Andrew Aguecheek in the RSC's 2012 production of Twelfth Night, directed by David Farr. In 2014 Mackinnon has appeared in Inside No. 9 for the BBC.Utopia (UK TV series) for Channel 4 and the Marvel Studios movie Guardians of the Galaxy (film).